The invention relates to a valve drive for piston internal combustion engines having at least one control cam, one additional cam, a first rocker lever and a second rocker lever which are pivotably mounted on a rocker lever support shaft, wherein the first rocker lever is in active contact with at least a first cylinder valve, at least the additional cam is in active contact with the second rocker lever, and the second rocker lever can be placed in force flux with the first rocker lever by means of an actuator element.
A brake device having a cam-actuated outlet valve is disclosed in DE 15 26 485. In this document, in addition to a customary rocker lever cam arrangement, an auxiliary rotational cam device is provided with a hydraulically actuated locking piston which, by actuating the locking piston arranged within the rocker lever, ensures the force flux between an auxiliary cam and the rocker lever.
In the document: Impressum, HONDA Deutschland GmbH, Öffentlichkeitsarbeit [publicity work], a rocker lever cam arrangement with a first control cam and a second control cam are shown on page 12. The control cams each have an operative connection to a cylinder valve by means of a lever which is pivotably mounted on a rocker lever shaft. A further rocker lever which can be connected in a positively locking fashion to the rocker levers by means of a driving actuator element is assigned to an additional control cam. The actuator element is moved axially with respect to the rocker lever axis here.
It is the object of the present invention to provide a valve drive in such a way that a flexible actuation of an engine valve is facilitated.